Stoking installation



July 5,1938. J, N VAN RlJSWIJK 2,122,733

STORING INSTALLATION Filed July 31, 1935 2 Sheets- Sheet 1 ZW'AMMMWOR.

' W MTORJIEZ Jill 5, 1938.

J: N. VAN RIJSWIJK STOKING INSTALLATION Filed July 31, 1935 2Sheets-Sheet 2 FIG? FIG; 3

- Patented July .5, 1938 PATENT OFFICE 2,122,733 STORING INSTALLATION.lacobus Nicolaas van Rljswijk, assilnor to Iron Netherlands,

s Gravenhage, Fireman Manufacturing Company, Portland, Oreg.

Application July 31, 1935, Serial No.

In the Netherlands August 16, 1934 2 Claims.

The invention relates to improvements in the so-called underfeed"staking-installations.

It is known by means of a driving-mechanism, which drives a feed-screw,to push coals from a coalbunker, placed between a driving-mechanism anda combustion-chamber, to said chamber.

Inthis arrangement the coalbunker, because it is of limited capacity,.must frequently be filled according to the varying consumption offuel,'

which is especially a drawback for central-heating-installations. It hasbeen already proposed to make the coalbunker of very large volume, whichnecessitates same being placed generally rather far from the boiler, andthus necessitates a long feed-screw and which causes thedrivingmechanism to be located far from the boiler. As thedriving-mechanism is generally provided with a ventilator built to it. avery long air-conmay be connected to dult then exists.

The object 01' this invention is to prevent the above disadvantages andprincipally consists therein, that the fuel is pulled (instead ofpushed) by a feed-screw from the coal-bunker to the combustion-chamber,which screw passes said chamber and is connected with the drivingmechanism. Thus the feed-screw reaches at theone end into thecoalbunker, while at the other end it is coupled to itsdriving-mechanism."

This embodiment has the advantage, that the driving-mechanism withventilator can be placed near to the boiler, and the regulation of thefire is thereby facilitated.

In order to prevent the part of the screw between the combustion-chamberand the drivingmechanism, towards which the coals are pulled, foulingand sticking fast, according to the in- .vention an opposite handedscrew, preferably with larger speed or pitch than the feed-screw, can belocated to this shaft part, the supplied coals being repulsed by saidopposite handed screw.

In order to remove regularly the coals under the shaft, according to theinvention, a projection such as a cam or blade preferably screwshaped,can be mounted to the shaft. Instead of this cam or wedge-shaped piececan be secured to the bottom of the flrepot.

The coals then are turned of! sideways, while Dulve In order to avoid ahigh temperature of the flre-box-walls, according. to the invention.said fire-box is water-cooled, and the cooling-Jacket the circulation ofthe cen 'tral-heating-installation.

This flrepot or box consists preferably of ingotblade, for this purposealso a rizing and dust-accumulation are prevented.

iron, but it also can be made of cast-iron or other metal.

.It has been found that with such a watercooled firepot no slack aflectsthe metal and the slack does not set hard in front of the air-openings,but is pressed upwardly by the fresh fuel and forms itself into a' flatannulus; which lies round the firepot. With such a firepot each iuel canbe stoked with high profitable efiect.

Finally according to the invention the combustion-chamber can also bewater-cooled, and the cooling jacket may be connected to thecentral-heating installation.

This combustion-chamber can be connected by a preferably cooledmain-flue with a fire door hole or an ash door hole of an existingboiler. The drawings which are in part diagrammatic illustrate theinvention by way of example.-

Fig. 1 is an elevation mainly in section of a combustion-feeding andstoking-mechanism according to the invention.

Fig. 2 is an elevation partly in section showing the mechanism appliedto a central'heating inwith a coalbunker located at a considerabledistance therefrom as shown by the break in the coal tube.

. Fig. 3 is an elevation taken at right angles to Flg. 2.

According to the illustrated construction a feeding screw. I is mountedin a tube 2 with the one end projecting into the bottom of thecoalbunker 3 (Fig. 2). This coalbunker can be at any place anddistancewith regard to the combustion-chamber 4, to which the coals have to besupplied. T'he-feedscrew mechanism 5, which is near thecombustionchamber 4 but on the opposite side of thecombustion-chamberfrom the coalbunker 3.

The feedscrew l passes the fire-box 6, which is under the chamber 4; Thefeedscrew has a part 'I with a thread adapted to move the coal to theright, said part lying between the coalbunker 3 and the flrepot 6, ends.part with an opposite screwthread 8, lying between the flrepot 6 and thefeeding-mechanism 5.

If the screwrotates, by the screwpart 1 from the coalbunker 3 to theflrepot 8, while the screwpart 8 takes care, that coal-dust does notpenetrate into the bearing of the screw-spindle and thedriving-mechanism, because it always pushes back the fuel into thefirepot i. Onthe part 8 of the screw passing through the firepot 8 is ascrew-shaped blade I 0, which serves to remove the coals from under theshaftpart 9 'on rotation of the screw.

l extends to a drivingthen the coals are pulled Fig. 1 further shows theair-box H, to which air can be supplied by a ventllator- 12 (Figs. 2 and3), which air can come through openings 53 in the combustion-chamber 5and through openings i l in the fuel in the firepot 6. In Figs. 2 and 3the motor is denoted by it.

From Fig. 1 it is seen that the firepot 5 is provided' with awater-cooling jacket it, which by means of tubes H, can b connected tothe circulation-installation of a central-heating arrangement.

The combustion-chamber 5 is located in a boiler 18 having an externalwall 69 which constitutes a watercooling jacket 26, which may beconnected through tubes 2i, 2% on the water circulation of acentral-heating arrangement.

The watercooled combustion-chamber 8, i8, is, 213 is connected to aboiler 23 (Fig. 3) with underfeed by means of a main-flue 22, which alsomay be water-cooled.

Preferably the tube 23, in which the screwpart 8 between the fire-box Sand the driving-mechanism 5 is located, is of air-tight construction.

The word surrounding in the claims means partially or completesurrounding.

I claimz- 1. In combination, a retort section having a curved coalpassage therethru receiving coal in a horizontal direction anddischarging the coal upwardly, a tuyere section adjacent the retortsection to form therewith a fire-pot, a tube forming'a cylindricalspaceintersecting the coal passage wall coaxially with the horizontallypositloned coal receiving end of the coal passage, a worm shaft having aright line axis extending through the horizontal portion of the coalpassage and also entirely through and beyond the cylinrical space whichintersects the coal passage wall, and flights of opposite pitch on saidworm shaft, one flight substantially fitting the horizontal portion ofthe coal passage and the other flight substantially fitting thecylindrical space formed by the tube so as to form a hearing for theworm shaft, and a motor for driving the worm shaft from the endextending through and beyond the cylindrical space.

2. A stoker fire-pot comprising a tuyere section and a retort section,said sections having an uywardly curved coal passageway therethru, apipe intersecting the curved passageway at one side, a coal conduitleading to the entry end of the curved passageway and coaxial with saidpipe but of larger diameter, a screw conveyor within the conduit forconveying coal from a coal storage space through said conduit to saidretort section, the shaft of said screw conveyor passing through thewall of the curved passageway and extending into the pipe, a reverselydirected flight on the extended portion of the shaft for preventing coalfrom passing through the pipe, and a motor for driving the .screw shaftfrom the end passing through the pipe,

1* eao onos HICOLAAS we: RUSWIJK.

